#include<stdio.h>
#include<stdlib.h>
#include<unistd.h>

int main()
{
	printf("before:PID is %d\n",getpid());
	pid_t id=fork();
	if(id==-1)
	{
		printf("fork error!!!\n");
	}

	printf("after:PID is %d,return is %d\n",getpid(),id);
	sleep(1);
	return 0;	
}
